Engine ignition means



Nav. 19, 1940. w. l.. NAWMAN ENGINE IGNITION MEANS 'Filed Feb. 17, 1959Err-1E- Rnv E L@ m M/ .m

Patented Nov. 19, 1940 UNITED STATES PTET OFFCE 1 Claim.

The invention relates to internal combustion engines and moreparticularly to an ignition means for internal combustion engines.

An object of the invention is to provide an ignition means for aninternal combustion engine which may be embodied as a sturdy, integralpart of the engine with all of the parts thereof confined entirely tothe engine cylinder and operated automatically by the movement lo of theengine piston to the head end of the cylinder' without the use of anyexternal mechanical or electrical parts as heretofore customarily reliedupon for igniting the compressed gas in the engine cylinder. 15 Anotherobject of the invention is to provide a simple and effective ignitionmeans of the character above which will provide a uniform ring of thecompressed gas throughout the entire combustion space of the cylinder.

.,0 The invention possesses other objects and features of advantage,some of which, with the foregoing, will be set forth in the followingdescription of the preferred form of the invention which is illustratedin the drawing accompanyg5 ing and forming part of the speciiication. Itis to :be understood, however, that variations in the showing made bythe said drawing and description may be adopted within the scope of theinvention as set forth in the claim.

30 Referring to said drawing:

Figure 1 is a vertical sectional view of a part of an internalcombustion engine embodying an ignition means constructed in accordancewith the present invention.

35 Figure 2 is a fragmentary sectional view showing one of the positionsof the parts of the ignition means.

Figure 3 is a sectional view similar to Figure 2 showing a secondposition of the parts of the ignition means.

Figure 4 is a sectional view similar to Figures 2 and 3, showing theparts of the ignition means in a third position.

Figure 5 is a vertical sectional view of an in- 45 ternal combustionengine showing a modified form f the ring means.

The ignition means of the present invention consists briey in theprovision of a chamber in the engine in communication with the engine 50cylinder and into and from which is reciprocated an auxiliary pistonwhich causes the compression and ignition of gases within the chamber,whereupon the ignited gases are passed into the engine cylinder toeffect an ignition of the gases 55 therein. In accordance with thepresent inven- (Cl. 12B-143) tion the aforementioned relativerecip-rocal movementI of the chamber and auxiliary piston is effected intimed relation to the movement oi the engine piston, whereby ignitionwill take place substantially at a top dead center position of theengine piston in the customary manner. Also, the chamber and auxiliarypiston are so formed as to cause a uniform discharge of the ignitedproducts entirely throughout the cornbustion space of the enginecylinder, thereby l0 eecting a most complete and effective ignition ofthe compressed charge of fuel in the cylinder.

With reference more specifically t0 the accompanying drawing, the engineand ignition` means therein depicted comprise an engine cas- 15 ing 6providing an internal engine cylinder 'i and formed with inlet anddischarge passages and 9 for the intake of fuel into the cylinder andthe discharge of spent products therefrom. Mounted in the passages 3 and9 are valves II 20 and l2 which are opened and closed in timed relationt0 the movement of the piston, so as to carry out the cycle of operationof the engine in accordance with the usual two or four cycle operation.Mounted within the cylinder I is an engine piston I3 which reciprocatesto and from the head end i4 of the cylinder to operate on the gases inthe cylinder in accordance with the cycle of operation of the engine.

The ignition means of the present invention comprises an auxiliarychamber i6 Whichis ar'- ranged in communication with the engine cylinder'and a plug member or auxiliary piston I1 which is adapted for movementinto and from the chamber to compress explosive gases in the chamber toa self-igniting pressure' and drive means is provided for causing therelative reciprocal movement of the member l1 and the chamber It intimed relation to the movement of the engine piston I3, so as to causean igni- 40 tion of the gases at a proper time in the operating cycle.

In the most simple embodiment of the invention as herein illustrated,the chamber I6 and the member I'I are provided on the piston and 45engine casing so that the reciprocation of the member I'I into and outof the chamber will be effected in proper timed relation to the movementof the engine piston itself, and without the use of any interveningdrive mechanism. In the form of the invention illustrated in Figures 1to 4, the chamber I6 is provided directly in the head end I8 of thepiston and the member I1 supported on the head end I 4 of the cylinder,while in the form of the invention illustrated in Figure 5,

the chamber I 6 is provided in the head end of the engine casing, whilethe member I'I is provided on the piston.

The chamber I 6, as illustrated in the accompanying drawing, is ofgenerally cylindrical shape and is provided-with a reduced neck portionI9 at the open end thereof. This latter portion is preferably ofcylindrical form and adapted for a sliding fit with a cylinder headportion 2| on the member II, whereby such head portion on engagementthrough the neck I9 will cause a compression of the gases containedwithin the chamber. In accordance with the present construction, thehead portion 2I has an axial length somewhat less than that of thechamber and is positioned immediately ahead of a reduced member portion22, whereby upon movement of the head 2l completely into the chamber asillustrated in Figure 4, the'portion 22 will become aligned with theneck I9, so as to define an annular passage between the portion 22 andthe neck for the cylindrical discharge of the ignited products withinthe chamber. As will be understood, the head portion 2l of the auxiliarypiston is of sufcient length relative to the length of the chamber andthe volume of the chamber to cause a compression of the fuel gasestherein to the point of self-ignition, whereby upon movement of the headportion 2l past the neck I9, such ignited gases will be allowed to passaround the head 2! and out through the annular passage defined betweenthe neck I9 and the reduced portion 22. vIn this manner a substantiallycontinuous sheet of re is discharged from the ignition means into allparts of the combustion chamber. Preferably, the axis of the chamber IBand that of the member I1 is coincident with the central axis of theengine cylinder, whereby the discharge of the ignited products will bemost effectively distributed throughout the combustion space of theengine cylinder and completely across the head end of the piston.

The several positions of the member I'I and chamber I6 are illustratedin Figures 2 to 4. In

Figure 2 the member I'I is about to enter the neck portion I9 of thechamber to compress the gases contained therein. In Figure 3 the headportion 2| is just passing to a detached position with respect to theneck I9 so as to open the annular passage aforesaid. In Figure 4 thepiston I7 is shown in fully inserted position into the chamber I6.

In the form of the invention illustrated in Figures 1 to 4, the pistonI1 is as aforementioned, mounted directly on the head casing of theengine cylinder. As here shown, the member is provided with a threadedshank 23 which is engaged through a threaded opening 24 in the head ofthe casing and is secured in position by means of a lock-washer 25 andnut 26 placed on the threaded shank at the exterior of the casing.

In the form of the invention as illustrated in Figure 5, the chamber I6'is embodied in the head casing as aforementioned. As here shown, thechamber is formed in an inserted piece 21 which is set in an opening 28in the cylinder head and secured in place b-y means of a lockwasher 29and nut 3l engaged with a threaded portion of the insert at the outerside of the casing. The auxiliary piston member I'I in this form of thevinvention is attached to the piston I3 for movement therewith and isconnected to the head end 32 of the piston in a curved conical base 33which connects the head end 32 of the piston to the reduced portion 22of the auxiliary piston. In this form of the invention compressedignited gases discharged from the chamber I6 now downwardly from thechamber in a continuous ring of fire and strike the downwardly andoutwardly curved surface 33, whereby the ignited gases are spreaduniformly across the entire combustion space of the engine cylinder andacross the head end of the piston. 'Ihis form of the invention isdescribed and claimed in a divisional application, vSerial No. 327,947,filed April 10, 1940.

I claim:

In combination with an internal combustion engine having a cylinder anda reciprocating piston therein and fuel inlet and discharge meansconnected to said cylinder, said piston having a chamber opening to thehead end thereof and formed with an internal cylindrical enlargement anda reduced cylindrical open portion at the outer end thereof, and amember projecting into the cylinder in alignment with said chamber andhaving a cylindrical portion thereof formed to slidably engage in saidreduced chamber portion to cause a compression and ignition of gases insaid chamber upon movement of said member portion therein, said memberportion and said enlargement being formed to dene a complete and uniformannular space around said portion in said chamber, said member having aportion of reducedcross-sectional area adjacent to said rst portionpositioned to register with said reduced chamber portion upon insertionof said first member portion into said chamber to provide an annulardischarge passage for conducting and dispersing the gases compressed insaid chamber into said cylinder.

y WILLIAM L. NAWMAN.

